1. Field
The presently disclosed subject matter relates to an optical semiconductor device module used in a head lamp or the like of a vehicle.
2. Description of the Related Art
Generally, in the same way as a chip resistor module and a chip capacitor module, an optical semiconductor device module or a light emitting diode (LED) module mounted on a vehicle is constructed by fixing an LED element and a coupler for leads to a mounting substrate. In this case, conductive terminals of the coupler are fixed to the mounting substrate using solder portions, screws or spot welds, which will be explained later in detail.
However, when the conductive terminals of the coupler are fixed directly to the mounting substrate using solder portions, screws or spot welds, cracks could occur in the solder portions, the conductive terminals could be deformed, or the coupler could be separated from the mounting substrate. This also will be explained later in detail.
Instead of directly processing or deforming conductive terminals of a coupler, other approaches are to put male terminals of a coupler onto female terminals of a mounting substrate (see: JP-2007-194172A), to sandwich a mounting substrate by clips of a coupler (see: JP-2007-207594A), to fix a coupler by an attachment to a mounting substrate (see: JP-2007-242267A), or to fix a coupler by leaf springs to a mounting substrate (see: JP-2007-200697A), thus supplying power from the coupler to the mounting substrate.
However, when the coupler is fixed to the mounting substrate by the coupling of the male terminals and the female terminals, the contact area between the male terminals and the female terminals cannot be increased, so that the male terminals on the mounting substrate could be separated therefrom. Also, in the coupler fixed by the clips on the attachment, the clips or the attachment may vibrate due to vibration of a vehicle, so that the LED element could be turned OFF. Further, when the coupler is fixed by the leaf springs, the leaf springs could be weakened under a high temperature state and the electrical contact therebetween could be weakened with time due to the one-point contact. In any case, lightening and darkening of the LED element may occur repeatedly.
Note that JP-2006-300877A discloses a measuring adapter for connecting alligator clips to a voltmeter, and JP-2005-209518A discloses a female terminal having rear side protrusions and front side protrusions providing two or more points of contact.